1. Technical Field
The present disclosure relates to a method of outputting temperature data in a semiconductor device and a temperature data output circuit, and more particularly, to a temperature sensing device of a semiconductor device that can rapidly sense and output temperature data at an initial stage of applying power, and a method of outputting temperature data using the same.
2. Discussion of Related Art
Modern semiconductor devices need high speed, a high degree of integration and low power consumption. For a semiconductor device installed in a battery-operated system such as a mobile apparatus, the characteristic of low power consumption becomes particularly significant.
Volatile semiconductor memory devices, such as DRAM in a semiconductor device, typically perform a refresh operation for recharging data at regular intervals to retain stored data, and the refresh operation consumes current. Since the data retention characteristic of the semiconductor memory device varies depending on temperature, when a refresh operation period is properly controlled according to temperature, power consumption due to refresh can be reduced. That is, when the semiconductor memory device is operated at low temperature, the refresh period can be set relatively longer than when it is operated at high temperature, resulting in reduced power consumption. To implement such low power consumption, a temperature sensor is installed in the semiconductor memory device, and a method of controlling the refresh period according to temperature data sensed by the temperature sensor is used.
In particular, attempts are being made to deliver temperature data in the semiconductor memory device to an internal or external controller such as a CPU or memory controller which would then control various operations of the semiconductor memory device according to the temperature data. For example, when the semiconductor memory device reaches over a predetermined temperature (e.g., 80° C.), the CPU makes a clock applied to or produced in the semiconductor memory device slow to prevent damage to the semiconductor memory device, thereby performing a stop function for reducing the temperature of the semiconductor memory device.